US5463871A - Side column cryogenic rectification system for producing lower purity oxygen - Google Patents

Side column cryogenic rectification system for producing lower purity oxygen Download PDF

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Publication number
US5463871A
US5463871A US08/317,973 US31797394A US5463871A US 5463871 A US5463871 A US 5463871A US 31797394 A US31797394 A US 31797394A US 5463871 A US5463871 A US 5463871A
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column
feed air
oxygen
passing
side column
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US08/317,973
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Harry Cheung
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Praxair Technology Inc
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Praxair Technology Inc
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Priority to US08/317,973 priority Critical patent/US5463871A/en
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Assigned to PRAXAIR TECHNOLOGY, INC. 39 OLD RIDGEBURY ROAD reassignment PRAXAIR TECHNOLOGY, INC. 39 OLD RIDGEBURY ROAD ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CHEUNG, HARRY
Priority to KR1019950033653A priority patent/KR100261915B1/ko
Priority to CN95102554A priority patent/CN1103041C/zh
Priority to DE69511028T priority patent/DE69511028T2/de
Priority to ES95115584T priority patent/ES2134391T3/es
Priority to BR9504263A priority patent/BR9504263A/pt
Priority to CA002159751A priority patent/CA2159751C/en
Priority to JP27822995A priority patent/JP3182326B2/ja
Priority to EP95115584A priority patent/EP0706020B1/en
Publication of US5463871A publication Critical patent/US5463871A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/04193—Division of the main heat exchange line in consecutive sections having different functions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04078—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression
    • F25J3/0409—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression of oxygen
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
    • F25J3/0429—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams of feed air, e.g. used as waste or product air or expanded into an auxiliary column
    • F25J3/04303—Lachmann expansion, i.e. expanded into oxygen producing or low pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04406—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system
    • F25J3/04418—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system with thermally overlapping high and low pressure columns
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/34—Processes or apparatus using separation by rectification using a side column fed by a stream from the low pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
    • F25J2200/54—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column in the low pressure column of a double pressure main column system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2215/00—Processes characterised by the type or other details of the product stream
    • F25J2215/50—Oxygen or special cases, e.g. isotope-mixtures or low purity O2
    • F25J2215/52—Oxygen production with multiple purity O2
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/02—Bath type boiler-condenser using thermo-siphon effect, e.g. with natural or forced circulation or pool boiling, i.e. core-in-kettle heat exchanger
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/04—Down-flowing type boiler-condenser, i.e. with evaporation of a falling liquid film

Definitions

  • This invention relates generally to cryogenic rectification and more particularly to the production of lower purity oxygen.
  • cryogenic air separation involves the filtering of the feed air to remove particulate matter and compression of that feed air to supply the energy required for separation. Following the compression the feed air is cleaned of high boiling impurities such as carbon dioxide and water vapor, cooled, and then separated into products by cryogenic rectification. The separation columns are operated at cryogenic temperatures to allow the gas and liquid contacting necessary for separation by distillation, and the separated products are then returned to ambient temperature conditions against the cooling feed air stream.
  • the most common cryogenic air separation system for the production of oxygen is the double column system which employs a higher pressure column and a lower pressure column in heat exchange relation at a main condenser.
  • the head pressure is the pressure discharge at the base load air compressor which is set by the pressure at the bottom of the higher pressure column plus the pressure drop in piping and apparatus between the base load air compressor and the higher pressure column.
  • the pressure at the bottom of the higher pressure column is set by the pressure drop of the stream from the top of the lower pressure column to the atmosphere, by the added pressure difference to the bottom of the lower pressure column, by the temperature difference across the main condenser which sets the high pressure nitrogen condensing pressure at the top of the higher pressure column, and by the added pressure drop to the bottom of the higher pressure column.
  • the pressure at the bottom of the higher pressure column is generally within the range of from 70 to 80 pounds per square inch absolute (psia) resulting in a head pressure generally within the range of from 77 to 87 psia.
  • the conventional double column system enables the separation of air with good energy efficiency and excellent product purity.
  • lower purity oxygen i.e. oxygen having a purity of 99 mole percent or less
  • the conventional system is less efficient because it has more air separation capability than is being utilized. Since the demand for lower purity oxygen is increasing in applications such as glassmaking, steelmaking and energy production, it is desirable to have a double column system which can produce lower purity oxygen at lower operating costs.
  • a cryogenic rectification method for producing lower purity oxygen comprising;
  • Another aspect of the invention is:
  • a cryogenic rectification apparatus comprising:
  • (E) means for passing fluid from the lower portion of the second column into the side column;
  • (G) means for recovering product from the side column.
  • distillation means a distillation or fractionation column or zone, i.e., a contacting column or zone wherein liquid and vapor phases are countercurrently contacted to effect separation of a fluid mixture, as for example, by contacting of the vapor and liquid phases on a series of vertically spaced trays or plates mounted within the column and/or on packing elements such as structured or random packing.
  • packing elements such as structured or random packing.
  • Vapor and liquid contacting separation processes depend on the difference in vapor pressures for the components.
  • the high vapor pressure (or more volatile or low boiling) component will tend to concentrate in the vapor phase whereas the low vapor pressure (or less volatile or high boiling) component will tend to concentrate in the liquid phase.
  • Partial condensation is the separation process whereby cooling of a vapor mixture can be used to concentrate the volatile component(s) in the vapor phase and thereby the less volatile component(s) in the liquid phase.
  • Rectification, or continuous distillation is the separation process that combines successive partial vaporizations and condensations as obtained by a countercurrent treatment of the vapor and liquid phases.
  • the countercurrent contacting of the vapor and liquid phases is generally adiabatic and can include integral (stagewise) or differential (continuous) contact between the phases.
  • Separation process arrangements that utilize the principles of rectification to separate mixtures are often interchangeably termed rectification columns, distillation columns, or fractionation columns.
  • Cryogenic rectification is a rectification process carried out at least in part at temperatures at or below 150 degrees Kelvin (K).
  • directly heat exchange means the bringing of two fluid streams into heat exchange relation without any physical contact or intermixing of the fluids with each other.
  • bottom reboiler means a heat exchange device which generates column upflow vapor from column bottom liquid.
  • turboexpansion and “turboexpander” mean respectively method and apparatus for the flow of high pressure gas through a turbine to reduce the pressure and the temperature of the gas thereby generating refrigeration.
  • upper portion and lower portion mean those sections of a column respectively above and below the mid point of the column.
  • feed air means a mixture comprising primarily nitrogen and oxygen, such as ambient air.
  • lower purity oxygen means a fluid having an oxygen concentration of 99 mole percent or less.
  • FIG. 1 is a schematic representation of one preferred embodiment of the cryogenic rectification system of this invention.
  • FIG. 2 is a schematic representation of another preferred embodiment of the invention wherein elevated pressure oxygen product may be produced.
  • FIG. 3 is a schematic representation of another preferred embodiment of the invention wherein feed air is provided for the higher pressure column at two pressure levels.
  • FIG. 4 is a schematic representation of another preferred embodiment of the invention employing a supercharged turbine.
  • the invention enables the higher pressure column of the double column system to operate at lower pressure by uncoupling the dependence of the pressure at the bottom of the higher pressure column to the oxygen product purity.
  • the invention achieves energy savings by reducing the feed air compression work required to achieve the requisite head pressure.
  • feed air 24 is compressed by passage through base load feed air compressor 25 to a pressure generally within the range of from 38 to 65 psia and then cooled by passage through cooler 26 to remove heat of compression. Thereafter the pressurized feed air 27 is cleaned of high boiling impurities, such as water vapor and carbon dioxide, by passage through purifier 28 and resulting feed air stream 1 is cooled by indirect heat exchange with return streams in main heat exchanger 70.
  • a minor portion 2 generally comprising from 10 to 25 percent of total feed air, is turboexpanded through turboexpander 80 to generate refrigeration, further cooled by passage through heat exchanger 71 and passed into lower pressure column 200.
  • Portion 3 generally comprising from 75 to 90 percent of the feed air, is passed through bottom reboiler 350 which is usually located within side column 300 in the lower portion of this column. Within bottom reboiler 350 the compressed feed air is at least partially condensed and thereafter the resulting feed air stream 29 is passed through valve 50 and into higher pressure column 100.
  • Higher pressure column 100 is the first or higher pressure column of the double column which also comprises second or lower pressure column 200.
  • Higher pressure column 100 operates at a pressure generally within the range of from 30 to 60 psia.
  • the feed air is separated by cryogenic rectification into nitrogen-enriched vapor and oxygen-enriched liquid.
  • Nitrogen-enriched vapor is passed in stream 4 to main condenser 250 wherein it is condensed by indirect heat exchange with lower pressure column 200 bottom liquid.
  • Resulting nitrogen-enriched liquid 31 is divided into streams 6 and 5.
  • Stream 6 is passed into column 100 as reflux and stream 5 is cooled by passage through heat exchange 72 and passed through valve 52 and into column 200 as reflux.
  • Oxygen-enriched liquid is withdrawn from the lower portion of column 100 as stream 7, cooled by passage through heat exchanger 73 and then passed through valve 51 and into column 200.
  • Column 200 operates at a pressure less than that of column 100 and generally within the range of from 16 to 25 psia.
  • Main condenser 250 can be the usual thermosyphon unit, or can be a once through liquid flow unit, or can be a downflow liquid flow arrangement.
  • Nitrogen-rich vapor is withdrawn from the upper portion of column 200 as stream 8, warmed by passage through heat exchangers 72, 73 and 70, and removed from the system as stream 33 which may be released to the atmosphere as waste or may be recovered in whole or in part.
  • Stream 33 will generally have an oxygen concentration within the range of from 0.1 to 2.5 mole percent with the remainder essentially all nitrogen.
  • Crude oxygen liquid having an oxygen concentration within the range from 50 to 88 mole percent, is withdrawn from the lower portion of second or lower pressure column 200 and passed as stream 10 into the upper portion of side column 300.
  • Side column 300 operates at a pressure which is similar to that of lower pressure column 200 and generally within the range of from 16 to 25 psia.
  • the descending crude liquid oxygen is upgraded by cryogenic rectification against upflowing vapor into oxygen product fluid and remaining vapor.
  • the remaining vapor generally having an oxygen concentration within the range of from 25 to 65 mole percent and a nitrogen concentration within the range of from 30 to 79 mole percent, is passed in stream 13 from the upper portion of side column 300 into lower pressure column 200.
  • the oxygen product fluid having an oxygen concentration which exceeds that of the crude oxygen liquid and within the range of from 70 to 99 mole percent, collects as liquid in the lower portion of side column 300 and at least a portion thereof is vaporized by indirect heat exchange against the condensing compressed feed air in bottom reboiler 350 which may be of the conventional thermosyphon type or may be a once through or downflow type unit. This vaporization serves to generate the upflowing vapor for the separation of the crude liquid oxygen within side column 300.
  • the oxygen product fluid may be recovered as gas and/or liquid. Oxygen product gas may be withdrawn from side column 300 as stream 11, warmed by passage through heat exchangers 71 and 70 and recovered as oxygen product gas 34. Oxygen product liquid may be withdrawn from side column 300 as stream 12 passed through valve 53 and recovered as oxygen product liquid 35.
  • the oxygen product fluid will have an oxygen concentration within the range of from 70 to 99 mole percent.
  • Table 1 lists the results obtained from a computer simulation of the invention carried out using the embodiment illustrated in FIG. 1.
  • the stream numbers in Table 1 correspond to those of FIG. 1.
  • This example of the invention is provided for illustrative purposes and is not intended to be limiting.
  • the higher pressure column comprises 20 theoretical trays
  • the lower pressure column comprises 22 theoretical trays
  • the side column comprises 8 theoretical trays.
  • the oxygen recovery is 97 percent of the oxygen contained in the feed air.
  • the head pressure required to carry out the cryogenic rectification in this example is only about 64 psia. This is about 18 percent less than the 78 psia which would be required to drive a comparable conventional double column separation, thus demonstrating the advantageous results attainable with the practice of this invention.
  • FIGS. 2, 3 and 4 illustrate other preferred embodiments of the invention.
  • the numerals in FIGS. 2, 3 and 4 correspond to those of FIG. 1 for the common elements and these common elements will not be described again in detail.
  • a portion 36 of feed air stream 1 is further compressed through compressor 37, cooled of heat of compression through cooler 38 and passed as stream 30 through main heat exchanger 70 and valve 56 into higher pressure column 100 at a point above the point where feed air stream 29 is passed into column 100.
  • Oxygen product liquid stream 12 is increased in pressure by means of liquid pump 60 and pressurized liquid stream 14 is vaporized by passage through main heat exchanger 70 to produce elevated pressure lower purity oxygen product gas stream 15.
  • the elevated pressure oxygen product gas will have a pressure within the range of from 30 to 300 psia.
  • a portion 20 of feed air stream 1 is further compressed through compressor 39 prior to passage through main heat exchanger 70 and bottom reboiler 350, while the remaining portion 32 of the feed air stream passes through main heat exchanger 70 but bypasses bottom reboiler 350 and is passed directly into column 100.
  • This embodiment enables one to more easily totally condense the feed air passing through bottom reboiler 350 and is advantageous when producing oxygen product having an oxygen purity within the range of from 90 to 99 mole percent.
  • feed air portion 2 is taken from stream 1 upstream of main heat exchanger 70 and compressed through compressor 90.
  • the resulting stream is cooled through cooler 91 to remove heat of compression and passed partially through main heat exchanger 70.
  • turboexpander 80 is directly coupled to compressor 90 serving to drive compressor 90 with energy released by the expansion of pressurized gas stream 2 through turboexpander 80.
  • This embodiment is advantageous from an equipment standpoint and can also be useful for producing oxygen product having an oxygen purity within the range of from 90 to 99 mole percent.
US08/317,973 1994-10-04 1994-10-04 Side column cryogenic rectification system for producing lower purity oxygen Expired - Lifetime US5463871A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US08/317,973 US5463871A (en) 1994-10-04 1994-10-04 Side column cryogenic rectification system for producing lower purity oxygen
KR1019950033653A KR100261915B1 (ko) 1994-10-04 1995-10-02 저순도의 산소를 제조하기 위한 사이드 칼럼 극저온 정류 시스템
CN95102554A CN1103041C (zh) 1994-10-04 1995-10-03 制备低纯氧气的副塔低温精馏系统
EP95115584A EP0706020B1 (en) 1994-10-04 1995-10-03 Side column cryogenic rectification system for producing lower purity oxygen
DE69511028T DE69511028T2 (de) 1994-10-04 1995-10-03 Kryogenes Rektifikationssystem mit Seitenkolonne zur Herstellung von niedrigreinem Sauerstoff
ES95115584T ES2134391T3 (es) 1994-10-04 1995-10-03 Sistema de rectificacion criogenica de columna lateral para producir oxigeno de menor pureza.
BR9504263A BR9504263A (pt) 1994-10-04 1995-10-03 Método e aparelho de retificação criogênica
CA002159751A CA2159751C (en) 1994-10-04 1995-10-03 Side column cryogenic rectification system for producing lower purity oxygen
JP27822995A JP3182326B2 (ja) 1994-10-04 1995-10-03 低純度酸素生成のための側コラム付き極低温精留システム

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US08/317,973 US5463871A (en) 1994-10-04 1994-10-04 Side column cryogenic rectification system for producing lower purity oxygen

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US5463871A true US5463871A (en) 1995-11-07

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US (1) US5463871A (zh)
EP (1) EP0706020B1 (zh)
JP (1) JP3182326B2 (zh)
KR (1) KR100261915B1 (zh)
CN (1) CN1103041C (zh)
BR (1) BR9504263A (zh)
CA (1) CA2159751C (zh)
DE (1) DE69511028T2 (zh)
ES (1) ES2134391T3 (zh)

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5596886A (en) * 1996-04-05 1997-01-28 Praxair Technology, Inc. Cryogenic rectification system for producing gaseous oxygen and high purity nitrogen
US5628207A (en) * 1996-04-05 1997-05-13 Praxair Technology, Inc. Cryogenic Rectification system for producing lower purity gaseous oxygen and high purity oxygen
US5675977A (en) * 1996-11-07 1997-10-14 Praxair Technology, Inc. Cryogenic rectification system with kettle liquid column
US5682766A (en) * 1996-12-12 1997-11-04 Praxair Technology, Inc. Cryogenic rectification system for producing lower purity oxygen and higher purity oxygen
US5836174A (en) * 1997-05-30 1998-11-17 Praxair Technology, Inc. Cryogenic rectification system for producing multi-purity oxygen
US5873264A (en) * 1997-09-18 1999-02-23 Praxair Technology, Inc. Cryogenic rectification system with intermediate third column reboil
US5881570A (en) * 1998-04-06 1999-03-16 Praxair Technology, Inc. Cryogenic rectification apparatus for producing high purity oxygen or low purity oxygen
US5916262A (en) * 1998-09-08 1999-06-29 Praxair Technology, Inc. Cryogenic rectification system for producing low purity oxygen and high purity oxygen
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FR2787559A1 (fr) * 1998-12-22 2000-06-23 Air Liquide Procede et installation de separation d'air par distillation cryogenique
FR2787561A1 (fr) * 1998-12-22 2000-06-23 Air Liquide Procede de separation d'air par distillation cryogenique
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WO2009136074A2 (fr) * 2008-04-22 2009-11-12 L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Procede et appareil de separation d'air par distillation cryogenique
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US5596886A (en) * 1996-04-05 1997-01-28 Praxair Technology, Inc. Cryogenic rectification system for producing gaseous oxygen and high purity nitrogen
US5628207A (en) * 1996-04-05 1997-05-13 Praxair Technology, Inc. Cryogenic Rectification system for producing lower purity gaseous oxygen and high purity oxygen
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EP0848218A2 (en) * 1996-12-12 1998-06-17 Praxair Technology, Inc. Cryogenic rectification system for producing lower purity oxygen and higher purity oxygen
EP0848218A3 (en) * 1996-12-12 1998-12-30 Praxair Technology, Inc. Cryogenic rectification system for producing lower purity oxygen and higher purity oxygen
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US5873264A (en) * 1997-09-18 1999-02-23 Praxair Technology, Inc. Cryogenic rectification system with intermediate third column reboil
US5881570A (en) * 1998-04-06 1999-03-16 Praxair Technology, Inc. Cryogenic rectification apparatus for producing high purity oxygen or low purity oxygen
US5934104A (en) * 1998-06-02 1999-08-10 Air Products And Chemicals, Inc. Multiple column nitrogen generators with oxygen coproduction
EP0962732A1 (en) * 1998-06-02 1999-12-08 Air Products And Chemicals, Inc. Multiple column nitrogen generators with oxygen coproduction
US5916262A (en) * 1998-09-08 1999-06-29 Praxair Technology, Inc. Cryogenic rectification system for producing low purity oxygen and high purity oxygen
FR2787559A1 (fr) * 1998-12-22 2000-06-23 Air Liquide Procede et installation de separation d'air par distillation cryogenique
FR2787561A1 (fr) * 1998-12-22 2000-06-23 Air Liquide Procede de separation d'air par distillation cryogenique
US6134915A (en) * 1999-03-30 2000-10-24 The Boc Group, Inc. Distillation column arrangement for air separation plant
US6237366B1 (en) 2000-04-14 2001-05-29 Praxair Technology, Inc. Cryogenic air separation system using an integrated core
US6295839B1 (en) 2000-04-14 2001-10-02 Praxair Technology, Inc. Cryogenic air separation system with integrated mass and heat transfer
US6295836B1 (en) 2000-04-14 2001-10-02 Praxair Technology, Inc. Cryogenic air separation system with integrated mass and heat transfer
US6279344B1 (en) 2000-06-01 2001-08-28 Praxair Technology, Inc. Cryogenic air separation system for producing oxygen
US6536234B1 (en) 2002-02-05 2003-03-25 Praxair Technology, Inc. Three column cryogenic air separation system with dual pressure air feeds
US20040020239A1 (en) * 2002-03-08 2004-02-05 Laforce Craig Steven Method of producing an oxygen-enriched air stream
US20050198958A1 (en) * 2002-04-11 2005-09-15 Haase Richard A. Water combustion technology - methods, processes, systems and apparatus for the combustion of hydrogen and oxygen
US8161748B2 (en) 2002-04-11 2012-04-24 Clearvalue Technologies, Inc. Water combustion technology—methods, processes, systems and apparatus for the combustion of hydrogen and oxygen
US6622520B1 (en) 2002-12-11 2003-09-23 Praxair Technology, Inc. Cryogenic rectification system for producing low purity oxygen using shelf vapor turboexpansion
US6626008B1 (en) 2002-12-11 2003-09-30 Praxair Technology, Inc. Cold compression cryogenic rectification system for producing low purity oxygen
US8268269B2 (en) 2006-01-24 2012-09-18 Clearvalue Technologies, Inc. Manufacture of water chemistries
WO2009071977A3 (en) * 2007-12-04 2011-05-26 Air Products And Chemicals, Inc. Thermosyphon reboiler for the denitrogenation of liquid natural gas
WO2009071977A2 (en) * 2007-12-04 2009-06-11 Air Products And Chemicals, Inc. Thermosyphon reboiler for the denitrogenation of liquid natural gas
WO2009136074A3 (fr) * 2008-04-22 2010-09-30 L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Procede et appareil de separation d'air par distillation cryogenique
WO2009136074A2 (fr) * 2008-04-22 2009-11-12 L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Procede et appareil de separation d'air par distillation cryogenique
JP2012529616A (ja) * 2009-06-12 2012-11-22 レール・リキード−ソシエテ・アノニム・プール・レテュード・エ・レクスプロワタシオン・デ・プロセデ・ジョルジュ・クロード 低温蒸留による空気分離のための装置及び方法
US20120125045A1 (en) * 2010-11-18 2012-05-24 Henry Edward Howard Air separation method and apparatus
US8899075B2 (en) * 2010-11-18 2014-12-02 Praxair Technology, Inc. Air separation method and apparatus
US20120125044A1 (en) * 2010-11-19 2012-05-24 Neil Mark Prosser Feed compression method and apparatus for air separation process
CN102538397A (zh) * 2012-01-18 2012-07-04 开封黄河空分集团有限公司 一种由空气分离制取氮气或制取氮气同时附产氧气的工艺

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ES2134391T3 (es) 1999-10-01
CN1126305A (zh) 1996-07-10
JP3182326B2 (ja) 2001-07-03
DE69511028D1 (de) 1999-09-02
KR960013411A (ko) 1996-05-22
KR100261915B1 (ko) 2000-07-15
EP0706020B1 (en) 1999-07-28
EP0706020A2 (en) 1996-04-10
CA2159751A1 (en) 1996-04-05
JPH08210769A (ja) 1996-08-20
CA2159751C (en) 1997-11-25
CN1103041C (zh) 2003-03-12
EP0706020A3 (en) 1996-07-03
DE69511028T2 (de) 2000-01-27

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